I recently purchased an Intex pure spa inflatable hot tub. The model I have uses a small salt cell, which has been pretty awesome since there's an app to control the scheduling of the swg... Anyway, a few days ago I started getting the e91 low salt error. Salt tested at 2500 ppm--optimal, according to the manual, added more to about 3,100 PPM and was still getting the error. Took the cell out, soaked it in vinegar a couple of times per manufacturer's recommendation, no dice. Tried diluted muriatic acid also. I don't appreciate any calcium on the cell's titanium blades, it looks brand new... Next I found a repair manual and opened her up. Repair manual states to test the voltage going from the transformer to the cell. Measured 11.1 vAC on that leg on the circuit board. Which it states should be 12 to 14 vAC.
Next I checked the voltage at the terminals going directly to the salt cell. It appears that the repair manual is recommending replacing a cell with a low salt error that measures over 11 vDC, also replacing a cell throwing a HIGH salt error with less than 5 vDC. My initial measurement of the cell in stock configuration was 7.7 vDC, which climbed up to 10.6 at the 2 hour mark.
I came across a thread on the site regarding hooking up an external power supply directly to the salt cell, so I tried that also.
I hooked up the external power supply (12v 5a DC) directly to the salt cell leads, and the voltage started where the stock configuration had left off, around 10.6 and climbed over 11 vDC before I shut it off. I could tell by the bubbles in the hot tub it was working to some degree. I'm just curious about the normal electrical operation of these, and if I am ruining my cell (which appears to be faulty already), or if the transformer may be to blame. Any insight would be much appreciated.
Also, I understand some units reverse the polarity from time to time, I tried that and the voltage still climbs, and exhibits the same "memory."
Next I checked the voltage at the terminals going directly to the salt cell. It appears that the repair manual is recommending replacing a cell with a low salt error that measures over 11 vDC, also replacing a cell throwing a HIGH salt error with less than 5 vDC. My initial measurement of the cell in stock configuration was 7.7 vDC, which climbed up to 10.6 at the 2 hour mark.
I came across a thread on the site regarding hooking up an external power supply directly to the salt cell, so I tried that also.
intex cell voltage, low salt error, and fix...
I have an Intex 8110 (IIRC) that was giving me low salt errors after confirming that the salt level is at 3200 ppm and that the plates are clean. I opened it up and started poking around with a meter and found that the DC voltage coming out of the rectifier and going into the board was low...
www.troublefreepool.com
I hooked up the external power supply (12v 5a DC) directly to the salt cell leads, and the voltage started where the stock configuration had left off, around 10.6 and climbed over 11 vDC before I shut it off. I could tell by the bubbles in the hot tub it was working to some degree. I'm just curious about the normal electrical operation of these, and if I am ruining my cell (which appears to be faulty already), or if the transformer may be to blame. Any insight would be much appreciated.
Also, I understand some units reverse the polarity from time to time, I tried that and the voltage still climbs, and exhibits the same "memory."
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